Rear Diff LSD

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costask2
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Rear Diff LSD

Post by costask2 »

Hi all,

I'm new to the forum and I´m really happy cause i´ve got so many answers and help by reading this forum.. Thanks for that.. :thnx

I just installed a s14 2.3 engine and gearbox to my 316 e21 (its my best project I´ve ever had) but I have a "small" issue? I´m running with the standard diff 4,10 and its really enoyng cause my top speed is 150 kph (90mph) at 7000rpm :rev ... its not drivable...

So my question is?

Im looking to fit a lower ratio diff and I can´t find any low enough for my taste from any e21, and I just wonder if I can use any diff from another BMW type like e30, or e36?? I´m looking for a ratio 3,25 or lower and 25% lsd...


I have been reading and searching a lot in the forum but I haven´t found anything that helps my... Look fwd for advice...

best regards

Kostas


-----BMW don´t follow the technology, BMW leads it-----

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harleytrike
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Re: Rear Diff LSD

Post by harleytrike »

i have a e21 3.64 but its not lsd if this helps
cobbler2u
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Re: Rear Diff LSD

Post by cobbler2u »

Ya sou costas
welcome to the forum and good luck with you new project
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costask2
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Re: Rear Diff LSD

Post by costask2 »

cobbler2u wrote:Ya sou costas
welcome to the forum and good luck with you new project
Jasou.. Thanks a lot.. :mrgreen:
-----BMW don´t follow the technology, BMW leads it-----

BMW e21 S14
BMW e46 325ti
BMW e38 740iL
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costask2
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Posts: 14
Joined: Tue Mar 15, 2011 4:36 pm
My E21(s): ´82 315 powered by s14
Location: Thessaloniki, Greece

Re: Rear Diff LSD

Post by costask2 »

harleytrike wrote:i have a e21 3.64 but its not lsd if this helps

Hi harleystrike,
thanks for the offer but I would like to get a lower ratio if possible.


as I can see, there is no lower than 3.45 which fitts e21 bolt on. I´m searching at different threads to see maybe there is any easy & cheep solution to use e30 or any other model to install in the e21 diff case but without success..
-----BMW don´t follow the technology, BMW leads it-----

BMW e21 S14
BMW e46 325ti
BMW e38 740iL
stefankj
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Re: Rear Diff LSD

Post by stefankj »

You need this and any small case lsd to mate it up with and swap it into the e21 casing. This is really the lowet ratio available for small case diffs.

http://www.ebay.de/itm/BMW-Differential ... 35b8853871
1982 315
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costask2
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Re: Rear Diff LSD

Post by costask2 »

Hi, thanks for the info.. so I just replace Pinion and Ring from a e30 or e36 small case? sounds perfect.. Is there any thread with this type of swap anywhere?
-----BMW don´t follow the technology, BMW leads it-----

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e21-Mark
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Re: Rear Diff LSD

Post by e21-Mark »

You can fit a 4:1 but any e30/e36 small case LSD requires the e21 case be modified to fit.
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